2010 Construction and Material Specifications - Ohio Department of ...

451.03
Provide machines capable of operating on two side forms, on adjacent lanes
of pavement and one side form or on two adjacent lanes as necessary. When
placing concrete adjacent to an existing pavement lane, take measures to protect
the adjacent pavement from damage. Remove from the work any machine that
causes displacement of the side forms from the line or grade or causes undue
delay, as determined by the Engineer, due to mechanical difficulties.
Finish small or irregular areas that are inaccessible to finishing equipment
using other methods as approved by the Engineer. Accomplish vibration of these
areas using hand held or machine mounted internal vibrators. Continue vibration
to achieve adequate consolidation, without segregation, for the full depth and
width of the area placed.
Use straight edge side forms made of steel and of a depth equal to the
specified pavement thickness. Do not use bent or damaged side forms or forms
with damaged joint locks or pin pockets. Clean and oil all forms each time they
are used. Provide forms in sections not less than 10 feet (3 m) in length, with
horizontal joint and base width equal to the depth of the forms. If the radius of the
circular pavement edge is 100 feet (30 m) or less, use flexible or curved forms of a
design acceptable to the Engineer. Provide adequate devices to securely set forms
and withstand operation of the paving equipment. Do not use built-up forms
except to construct pavement of a specified thickness whose total area for the
project is less than 2000 square yards (1650 m 2 ). Provide forms with adequate
joint locks to tightly join ends of abutting form sections together.
B. Slip Form Construction. Place concrete using a slip form paver or
combination of pavers designed to spread, consolidate, screed, and float-finish the
freshly placed concrete in one complete pass of the machine and with a minimum
of hand finishing to provide a dense and homogeneous pavement.
Consolidate the full width and depth of concrete pavement placed by a single
pass of a series of approved internal vibrators operating at a frequency range of
7000 to 11,000 impulses per minute. Attach vibrators to either the spreading or
finishing equipment in such a manner that they do not come in contact with preset
dowel basket assemblies, the subgrade, reinforcing mesh or side forms. Do not
operate vibrators in a manner to cause a separation of the mix ingredients
(segregation); i.e., either a downward displacement of large aggregate particles or
an accumulation of laitance on the surface of the concrete. Avoidance of
segregation of the concrete mix may require reduction in the vibration frequency
within the range specified when forward motion of the paver is reduced. Connect
the power to all vibrators so that they cease when the machine motion is stopped.
Stop paving operations if any vibrator fails to operate within the above specified
range.
Provide an electronic monitoring device that displays the operating frequency of
each internal vibrator on all paving machines used on mainline and ramp paving.
The monitoring device shall have a readout display near the paver operator’s
controls that is visible to the operator and the Engineer. Operate the monitoring
device continuously while paving and display all vibrator frequencies with manual
or automatic sequencing among individual vibrators. Using the monitoring system
record the following minimum information: time of day, station location, paver
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